Changes:
- Added support for a new article category: `webinar`.
- Added a template page for webinar articles.
- Added an additional route for webinar articles that users are taken to
to watch the webinar recording.
- Added `deliver-webinar-access-request`, an action that updates CRM
records when users fill out the form on the webinar template page.
- Updated the accepted `intentSignal` values in the
create-historical-event helper.
- Added an article for the "Beyond the hype, practical AI for device
management" webinar.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Public webinar pages (/webinars/:slug and /watch) with optional
embedded video and a new page template, script, and styles.
* Sidebar signup form (first name, last name, work email) with prefill
for signed-in users and improved scroll behavior.
* POST API to request webinar access: validates email domain, records a
webinar-request event, triggers background CRM sync, and returns a watch
view on success.
* Static-site build now recognizes webinar articles and enforces
embedded-video URL validation.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Copilot <[email protected]>
